Actually, the UHF (450 to 470) mobile Micor usually uses an IF of 11.7
Mhz. or 11.8 where multiple receivers are used. A 11.7 Mhz. oscillator is
mixed with the receiver injection frequency for transmitting simplex and a
16.7 Mhz. oscillator for the most common 5 Mhz. offset. The 405 to 420 Mhz
and 470 to 512 Mhz. Micors used slightly different schemes.
Even though the Micors are over thirty years old they will still hold
their own with anything built today and beat most. The Micor squelch is
classic, often imitated, never been bettered. The Micor receiver has been
the gold standard for a long time.
Al, K9SI
<snip>
> The channel element sets the RX frequency injection 21.4 MHz
> below the operating frequency. The same signal is sent to the transmitter
> board where it is mixed with another signal from the offset oscillator.
> If
> the offset oscillator is 21.4 MHz the radio will then transmit on the same
> frequency it receives on, ie simplex. If the offset oscillator is 26.4
> MHz
> the transmitter will generate a signal 5 MHz above the receive frequency
> for
> use on a repeater.
<snip>
